From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: KVM: MMU: optimize set_spte for page sync
Date: Wed, 10 Dec 2008 13:54:08 +0100
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Cc: kvm-devel <kvm@vger.kernel.org>,
	Eduardo Habkost <ehabkost@redhat.com>,
	Chris Wright <chrisw@redhat.com>
To: Avi Kivity <avi@redhat.com>
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On Wed, Dec 10, 2008 at 11:14:42AM +0200, Avi Kivity wrote:
> Marcelo Tosatti wrote:
>> Do you have objections for submitting this patch for 2.6.28 ? The hash
>> lookup kills performance of pagetable write + context switch intensive
>> workloads.
>>   
>
> Can you quantify?
>
> 2.6.28 is out of the question, 2.6.28.stable is possible, depending on  
> the actual performance difference.  I'd hate to introduce a correctness  
> problem just to improve performance.

Around 10% improvement on some workloads.